Charles burleigh



CHA RLES BURLEIGH, @F lllTCl-IBURG, MASSACHUSETTS.

Letters Patent N .-93,051, dated July 27, 1869.

INEPROVED STEAM AND AER-ENGINE.

The Schedule referred to iu these Lettere Patent and making part o che same.

To all whom may concern 13e known that I, CHARLES Besturen, of Fitchburg, in the county of 7Worcester, and State of Massailchusetts, have invented Improvements in Combined Steam and Air-Engines; and I do hereby declare that the ibllowing, taken in connection with th'ddrawings, which accompany and forni part of this specification, is a description oi my invention vsuliieient to enable those skilled in the art to practise it.

'in compressing air into a reservoir from which it is supplied to operate rock-drills and other engines, in snails, tunnels, deep-cuttings, and elsewhere, in situations where the use oi' steam would involve waste ei' iucl and inconvenience consequent upon condensation of thc steam, and where exhaust-steam would be inconvenient and often insupportable to the workmen employed, niuoli diiiiculty has been experienced in operating aivpuinps, because oi' the varying .resistance ollerec. to the air-condensing pumps, which resistance begins atnothing at the commencement of each stroke ci the pumps and terminates at the iull pressure sie isting in the air-reservoir.

@ne part of my intention consists in a peculiar arrangement of the crank of a steam-enginc with reference to the cranks of two air-pumps, by which, when the @logins-crank is moving past its dead-centres, and at its slowest rate of speed, the aiepuinp pistons are commencing their working strokes, and are performing the least amount of work required or" tirent in the act oiI compressing air, and when. the enginecranlrv is moving niost rapidly at about haii" of thedistance between its dead-centres, and when the steamion the steam-engine piston operates most effectively iifirotating the engine-crank,1lwair-pump cranks move with decreasing velocity, and so to bring their radii into line with 'the air-pump connecting-rods, so that said cranks and rods form, in eilect, toggle-jointe:which, in straightening, exert a most powcriiillieifect at the time when the resistance to the movement or the airpump pistons is greatest.

'ln compressing air, the latent heat therein is rendered sensible, and heats the working-parts of the pumps, which causes, by unegual expansion of the heated parts, unnecessary friction, leakage 'of valves, and other troubles and annoyances. i

it has been common to surround suchl pumps with a jacket, and to cause cold water to ilow. through the jacket and around the heated parts, abstracting from said parts seine of the caloric.

Another part of my invention relates toiau limproved method of applying water to absorb and carry o the heat generated or rendered sensible bythe action of the pumps in compressing the air, saiddmethod consisting in the introduction of water int'o'thel popup-cylV inders, so that it not only keeps the .i'parts of thepunips from becoming heated, but also |performs the oiice of a lubricant, checks and diminishes air-leaks, by occupying anditscli'leaking through spaces, through which air would otherwise pass, and prevents the eduction-valve from slamming upon its seat, by allowing it to settle no faster than the movement ofthe pump-piston in its receding stroke..

. The drawing shows, in-

Figure l, a vertical sectional elevation of an an'- compressing engine, embodying the improvements comprised in my present invention.

Figure 2 showing, partly in plan, the common toppiece or chest, into which both pumps discharge air, the covers of the chest being removed, showing one eduction-valve, thepther eductioii-valve being removedfor the purpose ci' exhibiting the induction-valve, which is seated on the air-pump piston.

' The pumps shown are single-acting, and are .are ranged vertically, so that the valves connected there ivith operate, in closing, by gravity alone, unaided by springs,botli pumps acting to compress air by the up4h Ward strokes of their pistons, which pistons are made long, and are open at their lower ends, so that' the airf pump connectingrods enter the pistons and take hold of wrist-pins located as nearly as may beto the indue tionvalve seats, this arrangement obviating any ne cessity of the employment oi" cross-heads and ways or slides.

The steam-engine and air-pumps have one shaft in common, which is cranked for the pumps, the pumpcrank wrists being in the same plane, one hundred and eighty degrees apart from each. other, the steam-engine crank-Wrist being secured in a ily-wheel on one end of the shaft and about forty-ve degrees in ada vanoe or lead in the direction of rotation from one of the pump-crank wrists, and about two hundred and twenty-iive degrees in advance of the other pump-- cranlrwrist in the same direction.

The steam-engine cylinder may be located as is most convenient, either horizontally, as shown, or it may be placed vertically or inclined, the only matter of importance, as bearing on to the steam-engine, being that itscrank-pin orwrist shall. have substantially the speciied relation to the cranlopins pr wrists of the air-pumps.

1n the drawingsc is the bed-plate, having therein the bearings for theV cranked shaft t, common to the pumps and the steamengine, the crank-wrists for the pumps being denoted by c and d, and the steam-engine crank-wrist or pin by e.

v lhe pump-cylinders f and g are supported on a suitable frame-Work, directly over the crank-shaft, and are open at their lower ends, being bored of uniform diameter throughout their length.

0n the top ilau'gesl ofthe pump-cylinders a plate, h, is fitted, in which two circular openings' are made this invention in respect" concentric with the pump-cylinders, said plate serving as the seat for each of' the eduction-valves i, which are of c e poppet variety, and are guided in their vertical movements by stems fitting in sleeves made in the covers j, which close the openings formed in the air-chest k, which covcrsthe plate h, and is common to both pump-cylinders, and connects and strengthens the top of the machine.

The air-pump pistons l are made as long hollow cylinders, open at both ends, the upper end ci' each havin a flange, which projects slightly inward, a spider being cast in thc uppeil end of each piston, which serves to'receive a wrist-pin, m, and the guide and Vcheck"spindle of the inlet-valve n, which is of the poppet variety, and has its seat on the inwardly-proj ecting flange before mentioned.

The wrist-pins m are connected to the crank-pins c and (l, by connecting-rods 0,' so that as shaft b is rots ted in ille i direction indicated by the arrows seen in Iig. 1the air-pump pistons Z are reeiprocated in an ibvious manner, the valves n lifting as the pistons desconti, admitting air past the spiders in the pistons, and. past the openings in the pistons controlled by the valves n, into the air-pump cylinders f and g, and when tbe pistons Zrise in the air-pump cylinders, the vulves n having closed by their own weight, the air above said 'valves is compressed until its elastic force is sufficient to overcome the weight of valve t, and the pressure of the air stored in the receiver beyond.

The opening oi'I valve i occurs, sooner or later, `before the pistons Z arrive at the highest points in. their stroke, according to the weightoi'.' valve o, and the pressure existing in ille chest It, and the reservoir beyondl The chest k communicates, with any suitable airtank or receiver, by means oi' a pipe, p.'

The pipe q serves to convey water to each pump, said pipe being branched to deliver between the valves n. and/i, so that the -water will rest on the tops et' the pistons n, in their ascent, and will lubricate the entire surfaces of the pump-cylinders, and will check thean from escaping through small leaks when the ,pistonm packings are imperfect; the water also fills any clearances which exist between the valves 'i and n, and affords a body on which the valves 'i rest, and by which they are gently lo vered upon their seats, as they descend,'when the pistons l move downward,

The water also takes up the heat given out by the air asit is condensed and as itis generated by the force employed, and any excess of water and the vapors arising therefrom, are forced with the condensed air beyond valves fi, iuto the receiver or tank, where the Water settles to the'bottom and is drawn olil by means of a valve operated by a float in a well-known manner.

The water may be supplied frein a 'sufficient head to enter the pumps at times when little or no pressure present, a suitable check-valve being arranged in pipe q to prevent escape of airand backward ilow oi" the water, or it may be supplied in jets from a pump properly timed and ot' the right capacity to deliver only the requisite quantity.

No harm results from allowing the water to drip from the open ends of the punip-cylimlers upoirthe cranks beneath. l

l cle-im the arrrugelnent of cranks which make en tire rotations, suhmiially as herein specified, in the combination oi' a itesm-engine with singlemcting aircompressing pumps.

Also, devices for introduction of water into vertical air-compressing pumps, arranged to deliver the water between the tops of the pompqiistons and the pumpdelivery valves, substantially as hereinv specified.

` HARLES BURLEIGI'.

Witnesses .L B. Gnocca', FnANoIs 'i'fonnn 

